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Thread: More from Arp et al.

  1. #1381
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    Quote Originally Posted by turbo-1
    Antoniseb - I have told you before, do not be shy about asking me questions just because you are a moderator.
    I understand, however, your acceptance of me asking questions doesn't preclude there being some objection. nereid is not moderating because of such an objection.
    Forming opinions as we speak

  2. #1382
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    Quote Originally Posted by antoniseb
    I understand, however, your acceptance of me asking questions doesn't preclude there being some objection. nereid is not moderating because of such an objection.
    Gotcha...somebody else might complain. Well, I can't control that, so do what you must.

  3. #1383
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    Quote Originally Posted by turbo-1
    Every single one of M81's smaller neighbors has an excess redshift WRT the host. Every one. Newman and Terzian said that there is a one in 12 chance that this can occur because there are 12 galaxies involved, totally ignoring the gravitational influence of the much larger host galaxy.
    M81 could easily be a special case. It has just recently had a close interaction with M82, and M81 is flying in our direction, and M82 going the other way. The smaller galaxies around M81 might well be physically moving away from us faster than M81. Are there any little galaxies around M82? I'd guess they would mostly be moving toward us. How about M33, or M31, or any of the other galaxies near us. Lets see some statistics about them before pointing to M81 and calling it typical.

    N&T concluding that there is a one in 12 chance because there are twelve galaxies seems like odd math. If we treat it as a binary thing that galaxies are coming or going, wouldn't it be one chance in 2 to the 12 (1/4096)?
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  4. #1384
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    Quote Originally Posted by antoniseb
    M81 could easily be a special case. It has just recently had a close interaction with M82, and M81 is flying in our direction, and M82 going the other way. The smaller galaxies around M81 might well be physically moving away from us faster than M81. Are there any little galaxies around M82? I'd guess they would mostly be moving toward us. How about M33, or M31, or any of the other galaxies near us. Lets see some statistics about them before pointing to M81 and calling it typical.
    Perhaps someone here will volunteer to do a NED survey of differential redshifts of galaxies with small companions in preparation for this future sub-thread?

    Quote Originally Posted by Antoniseb
    N&T concluding that there is a one in 12 chance because there are twelve galaxies seems like odd math. If we treat it as a binary thing that galaxies are coming or going, wouldn't it be one chance in 2 to the 12 (1/4096)?
    Very odd math, indeed. It's actually worse than you think, because some of the companions should be moving perpendicular to our line of sight (little or no differential within the error of the spectroscopy), some should be moving away from us relative to M81 and some should be moving toward us, so the chance of any particular galaxy being redshifted relative to M81 is probably more like one in 3. The numbers get big pretty fast if you constrain the observations a bit vs a simple binary choice. If I punched in the right number of "3s" on my little $2 calculator 312 is 531,441 - pretty long odds.
    Last edited by turbo-1; 2006-Apr-15 at 04:05 PM.

  5. #1385
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    Quote Originally Posted by antoniseb
    I understand, however, your acceptance of me asking questions doesn't preclude there being some objection. nereid is not moderating because of such an objection.
    Since I was the one that brought up the "conflict of interest issue" and since it subsequently got blown out of proportion, let me state here that I have no concern whatsoever about you having a deeper involvement in this discussion.

  6. #1386
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    Quote Originally Posted by dgruss23
    Since I was the one that brought up the "conflict of interest issue" and since it subsequently got blown out of proportion, let me state here that I have no concern whatsoever about you having a deeper involvement in this discussion.
    Thanks dgruss23. I will be involved, as is inescapable by my reading the thread and caring about it, but I will continue to mostly ask clarification and softball type questions... When I see something that doesn't make sense, as opposed to something where I'd be really trying to break Arp's model.

    This recent case of questioning the use of M81 is about as far as I am comfortable going, but I assume that when the holiday is over, you'll be seeing the usual mainstreamers in probing a little deeper.
    Forming opinions as we speak

  7. #1387
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    Quote Originally Posted by antoniseb
    In the meantime, the Milky Way has quite a few companions (some of which are embedded within our galaxy, and have long tails or bridges connected to them). Do you think that any of them are showing intrinsic red shift? Certainly if all companion galaxies are fleeing, we should see a preponderance of evidence that our companions are mostly redshifted, but it is my understanding that they are not. Similarly, M31 has several comapnions, and they too do not seem to have a bias toward being red-shifted.
    Here are couple of papers addressing your argument (I believe that all these papers have been mentioned in this thread before):


    It is important to notice that dwarf companion galaxies are not required to show the excess redshift in companion galaxies -trend (Arp suggests that they are same aged material as the main galaxy). Major companion galaxies of M31 are indeed all redshifted relative to M31.

    (Earlier in this thread I did some calculations on M31 system.)

  8. #1388
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    I just surveyed NED for another stretch of interacting galaxies from Arp 194 through Arp 202 to see if the notion that the smaller companions of interacting pairs holds with galaxies of differing morphology (not holding strongly to the "bridge, spiral arm connection"), just looking for apparently interacting galaxies in which one member is substantially larger than another to make the comparison.

    Code:
    Arp #    excess redshift (companion)
    194      -79
    195a-b  343
    195a-c  182
    196       ?
    197       ?
    198       38
    199       39
    200       ?
    201       -53
    202       4
    In these 10 associations there are 3 pairs for which NED has no redshift data for the companion, there are 2 pairs in which the host has the extra redshift, with an average differential velocity of -66 km/s. In the remaining 5 associations (Arp 195 has two smaller companions) the smaller companions have the extra redshift, with an average diffferential velocity of 121 km/s.

    This is a very tiny sample, but it closely follows the trend set by the bridged galaxy pairs that I surveyed previously. There are about twice as many redshifted companions as redshifted hosts, and the group with redshifted companions showed about twice as much differential velocity. These galaxy pairs meet the broad definition for "bridged" galaxies, since most of the companions appear to be ejected or are still in apparent contact with the host.

    To avoid confusion, I will not add these to the redshift differential table of bridged galaxies. The point is moot anyway, since adding these would essentially change nothing of importance. The relative abundances of redshifted companions would still be ~2x that of redshifted hosts, and the velocity differential of the "redshifted companions" group would still be ~2x that of the group with redshifted hosts.
    Last edited by turbo-1; 2006-Apr-15 at 06:48 PM.

  9. #1389
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    OK, it's a rainy day, so I went back to the very deep exposure of M100 (NGC 4321-easy to remember!) that I linked earler.

    http://www.aao.gov.au/images/deep_html/n4321_d.html

    The small elliptical (NGC 4323) at the 11:00 position appears to have been ejected from M100, since it is on the end of a tidal streamer that points back at the core of M100. I went to NED for the HC velocities: M100=1571 km/s NGC 4323=1803 km/s so the bridged companion has an excess differential of 232 km/s. Certainly within the realm of peculiar motion, but of course it is a much larger differential than the average differential in which the hosts have the excess (~65-75 km/s from my modest samples to date), so at least some of the redshift may be intrinsic.

  10. #1390
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    Quote Originally Posted by turbo-1
    it is a much larger differential than the average differential in which the hosts have the excess (~65-75 km/s from my modest samples to date), so at least some of the redshift may be intrinsic.
    I don't know if that makes it intrinsic, but once again, the smaller unit is going away from us relative to the big one.
    Forming opinions as we speak

  11. #1391
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    Quote Originally Posted by antoniseb
    I don't know if that makes it intrinsic, but once again, the smaller unit is going away from us relative to the big one.
    A disturbing trend! Does our Sun have bad breath or B.O.? The companions seem to be avoiding us quite diligently if we believe NED's heliocentric velocities.

  12. #1392
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    Quote Originally Posted by turbo-1
    The small elliptical (NGC 4323) at the 11:00 position appears to have been ejected from M100, since it is on the end of a tidal streamer that points back at the core of M100.
    What evidence do you have to suggest 4323 was "ejected" from M100 as opposed to the explanation that it is simply interacting with M100? And again, what do you mean by "ejected"? Are you claiming that 4323 didn't exist until it was suddenly spat out from the nucleus of M100? Why suggest a scenario that would apparently require a violation of physical law when there is such a simpler and physically plausible explanation that these are two galaxies that have interacted in the past via gravitational dynamics?
    Everyone is entitled to his own opinion, but not his own facts.

  13. #1393
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    Quote Originally Posted by Cougar
    Why suggest a scenario that would apparently require a violation of physical law when there is such a simpler and physically plausible explanation that these are two galaxies that have interacted in the past via gravitational dynamics?
    That's a fair question Cougar. The answer is that if all examples were exactly like this specific example (relatively small redshift differences) then there would be no need for an ejection scenario because normal gravitational dynamics would be sufficient to account for it.

    But as you are quite familiar with by now, we have examples such as NGC 7603 and others that I have not yet brought forward that have much larger redshift differences. There is also the large suite of observations that have led to Arp's empirical model - which is an ejection model.

    So all Turbo-1 is doing is putting this relatively local example with a mild redshift difference in the context of that model - because other examples exist which suggest an ejection scenario might be one way to explain what is observed.

  14. #1394
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    While we are waiting for additional arguments from the mainstream proponents, I think this paper is another good reference on this issue. It provides some additional examples of pairs in which there are large redshift differences. AM2006-295 is very interesting.

    In this paper there are 4 examples with very large redshift differences (including NGC 7603) and it is definitely worth a look at Figure 4 (Plate 8) at the end of the pdf.

    Both papers talk about spectral peculiarities associated with these galaxies.

  15. #1395
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    Quote Originally Posted by Cougar
    What evidence do you have to suggest 4323 was "ejected" from M100 as opposed to the explanation that it is simply interacting with M100?
    Simply interacting? How does a dwarf elliptical sitting out in the fringes of a large spiral galaxy pull a thin straight tidal stream of stellar material out of the larger host? If you can show me how this can happen, you're going to meet the king of Sweden. The only way that the DE can overcome the gravitational hold of the spiral on its stellar material is through proximity to the material (remember the inverse square relationship for gravity). This tells us that the DE has made a pass through a densely-populated zone of the host galaxy and stripped out material along the way. If you don't like the ejection scenario, you will have to postulate a bulls-eye type collision in which NGC 4323 passed through the disk of M100 and is now seen exiting.

    Edit: If you embrace the bulls-eye collision as a means to reject ejection, you will have to explain the large number of such precise collisions that have resulted in tidal streams point back pretty directly at the core of the host galaxy. Which is more likely-ejection (in which the tidal stream should point back to the core, at least until differential rotation distorts the stream) or lots of near-perfect bulls-eyes?

    Quote Originally Posted by Cougar
    And again, what do you mean by "ejected"? Are you claiming that 4323 didn't exist until it was suddenly spat out from the nucleus of M100? Why suggest a scenario that would apparently require a violation of physical law when there is such a simpler and physically plausible explanation that these are two galaxies that have interacted in the past via gravitational dynamics?
    Memory problems? From post 1325:
    Quote Originally Posted by Cougar
    As far as the "ejection" idea is concerned, this would seem to be a viable mechanism not requiring any new physics. I haven't done the computer modeling, but it seems to me even a close two-body interaction between nuclei could provide a possibility. This could not only yield an ejected object, but could conceivably leave behind a highly disturbed AGN or "Seyfert" galaxy, which would account for that perceived correlation.
    Last edited by turbo-1; 2006-Apr-16 at 03:11 PM.

  16. #1396
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    I have extracted all the redshift differentials from the tables above, and have cast out all the zero differentials and all the differentials larger than 1000 km/s. The remaining differentials are listed in the column below. The very last number of the column is the average of these differentials. There are 12 differentials with a negative sign, indicating the magnitude of the excess redshift exhibited by the larger host galaxy. The 24 positive numbers are the magnitudes of excess redshift exhibited by the smaller companion. Without a contribution to these apparent heliocentric velocities by an intrinsic redshift, these differentials should be split evenly with about half of the companions approaching us and half receding WRT to the hosts. This is obviously not the case. I took the average to see where the mid-point of the data should be. It appears that about 75 km/s is the mid-point.

    excess V..km/s
    -260
    -180
    -156
    -96
    -79
    -53
    -21
    -19
    -18
    -7
    -6
    -4
    2
    4
    6
    18
    28
    38
    39
    39
    41
    59
    71
    81
    97
    123
    182
    198
    275
    291
    293
    336
    343
    348
    354
    361
    75.77777778

  17. #1397
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    Quote Originally Posted by turbo-1
    Simply interacting? How does a dwarf elliptical sitting out in the fringes of a large spiral galaxy pull a thin straight tidal stream of stellar material out of the larger host?
    The dwarf is not "sitting" out there. It is in motion. A billion or so years ago it apparently wandered within the gravitational pull of M100 and swung around it something like a comet swings around the sun. I notice the tidal stream is very diffuse, hardly noticeable in certain wavelengths. This collision was apparently not a direct hit or even a near miss, but rather a far miss.

    Quote Originally Posted by turbo-1
    If you can show me how this can happen, you're going to meet the king of Sweden.
    I'll tell him I owe it all to the BAUT forum.

    Quote Originally Posted by turbo-1
    The only way that the DE can overcome the gravitational hold of the spiral on its stellar material is through proximity to the material (remember the inverse square relationship for gravity). This tells us that the DE has made a pass through a densely-populated zone of the host galaxy and stripped out material along the way.
    When a baseball player gets ejected from a ball game, he first had to be in the game, and then he was thrown out. When a galaxy makes "a pass" by another galaxy, the galaxies are said to be interacting or colliding. To be ejected from the nucleus of a galaxy implies that the dwarf or quasar or whatever object began its existence in that nucleus and was thereafter ejected (for some inconceivable reason). "Ejection" is an Arpian buzzword that I think needs to be, if not explained, at least well defined.

    Quote Originally Posted by turbo-1
    If you don't like the ejection scenario, you will have to postulate a bulls-eye type collision in which NGC 4323 passed through the disk of M100 and is now seen exiting.
    Why do you think a "bull's-eye" is required. I would think any "fly-by" within a very wide range of proximities would quite suffice.

    Quote Originally Posted by turbo-1
    Quote Originally Posted by Cougar
    And again, what do you mean by "ejected"? Are you claiming that 4323 didn't exist until it was suddenly spat out from the nucleus of M100? Why suggest a scenario that would apparently require a violation of physical law when there is such a simpler and physically plausible explanation that these are two galaxies that have interacted in the past via gravitational dynamics?
    Memory problems? From post 1325: Originally Posted by Cougar: "...it seems to me even a close two-body interaction between nuclei could provide a possibility. This could not only yield an ejected object, but could conceivably leave behind a highly disturbed AGN or "Seyfert" galaxy, which would account for that perceived correlation."
    Yes, I recall trying to provide some plausible explanation for these observations. But this doesn't answer my question to you. What is your explanation?
    Everyone is entitled to his own opinion, but not his own facts.

  18. #1398
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    Quote Originally Posted by turbo-1
    Simply interacting? How does a dwarf elliptical sitting out in the fringes of a large spiral galaxy pull a thin straight tidal stream of stellar material out of the larger host?
    There have been a few news stories lately about small galaxies getting consumed by the Milky Way. In the cases shown, there are thin straight tidal streams coming out of the small elliptical core which follow the path of the little galaxy's orbit around ours: one stream leading, and the other trailing behind. It sounds like you have this backward.
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  19. #1399
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    Quote Originally Posted by Ari Jokimaki
    Quote Originally Posted by Cougar
    I've got a lot more to comment on, particularly on the behemoth Corredoira, Gutierrez paper, which I think deserves a lot of criticism, but that will have to wait because.... I'm going skiing.
    04-April-2006:
    Quote Originally Posted by Cougar
    But let's get away from the generalities and look at some specifics. I still want to discuss the newer Lopez-Corredoira and Guitierrez paper that you linked to regarding NGC 7603... if I have time tomorrow.
    04-April-2006: a comment about a certain Lopez-Corredoira & Gutierrez gravitational lensing related statement followed by:
    Quote Originally Posted by Cougar
    Well, that's not about the bridge either. It's about the paper, which I find riddled with flaws. Maybe I'll have time tonight to express my criticisms of the authors' bridge assertions.
    05-April-2006:
    Quote Originally Posted by Cougar
    Plus, one of the few good points of the L-Corredoira, Gutierrez paper was how they mentioned that we tend to view interacting objects as if they are in the two-dimensional plane of the sky as viewed from Earth, which they are not.
    And now this:
    Quote Originally Posted by Cougar
    According to one paper written by authors with a clear Arpian bias.
    It's becoming obvious that you don't have anything substantial to say about Lopez-Corredoira & Gutierrez paper. These comments are meaningless if you don't tell what the bias/flaws are. (Well, there's one possible meaning for comments like these; trying to make the paper look bad, even if it's not.)
    Excuse me for getting sidetracked. Let me reiterate: The Lopez-Corredoira, Gutierrez paper is riddled with flaws. Let's list a few of those flaws:

    • First, the grammar in this paper is atrocious. This alone is enough for this paper to be rejected. A journal editor would likely tell the authors to have it edited and resubmit it.
    • Much more importantly, the authors acknowledge the argument against a posteriori statistical analysis, but then they proceed with such an argument anyway. On page 17 they state, "Statistics have been calculated in several ways for some time concerning the anomalous redshift problem (e.g., Arp 1981, 1999a; Burbidge et al. 1997), in order to assess the probabilities of peculiar configurations. However, many other authors (e.g., Noerdlinger 1975; Sluse et al. 2003) have suspected that many of these calculations are unappropriate. Some authors also say that one should not carry out a calculation of the probability (“a posteriori probability”) for an a priori known configuration of objects (for instance, that they are aligned, or that they form a certain geometrical figure) because all possible configurations are peculiar and unique." This type of probability calculation is much like flipping a coin 100 times, recording the outcome of each flip, and then claiming that the probability of that particular sequence of flips is extremely unlikely, i.e., 1 chance out of 2100. The authors attempt to deflect this criticism by claiming that since their a posteriori argument can be shoehorned into "a physical process in an alternative theory", then it should be exempt from such criticism. Nevermind that such so-called "physical process" is unobserved, unexplained, and unsupported. The authors' defense of their statistical methods is fatally flawed, leaving the "improbability" of their statistical arguments meaningless.
    • The authors continue for page after page asserting the improbability of such a configuration. However their entire statistical/probabilistic argument has been fatally undercut by the 2005 paper by Scranton, Menard, et al.. Simply put, new data has come forward, and the conclusions that L-Corredoira, Gutierrez have worked so hard to establish are now seen as simply invalid.
    • In summary, the authors state, "[We have found] several signs of irregularities and asymmetries towards the east. Neither these eastern asymmetries nor the filament towards the east, apparently connecting NGC 7603 and NGC 7603B, can be easily understood in an isolated galaxy..." This appears to be an argument from incredulity, therefore any conclusion reached is drawn from a logical fallacy.
    • Are statements like the following appropriate in a scientific paper? "The (possible, although not sure) detection of vigorous star formation observed in the HII-galaxies of the filament, if confirmed, would have a probability 2 × 10−4..."

    I don't need to try to make this paper look bad. It is bad.
    Everyone is entitled to his own opinion, but not his own facts.

  20. #1400
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    Quote Originally Posted by Cougar
    The dwarf is not "sitting" out there. It is in motion. A billion or so years ago it apparently wandered within the gravitational pull of M100 and swung around it something like a comet swings around the sun. I notice the tidal stream is very diffuse, hardly noticeable in certain wavelengths. This collision was apparently not a direct hit or even a near miss, but rather a far miss.
    I realize that the dwarf is moving, and it is moving directly away from the core of M100, judging from the nice straight tidal stream pointing in that direction. What observations can you cite to support your assertion that this was not a direct hit, nor a near miss, but a far miss? I don't see how you manage to derive this from the evidence I linked. Do you have additional observations that you will share?

    Quote Originally Posted by Cougar
    I'll tell him I owe it all to the BAUT forum.
    We all owe a lot to this forum. I hope that it thrives and grows.

    Quote Originally Posted by Cougar
    When a baseball player gets ejected from a ball game, he first had to be in the game, and then he was thrown out. When a galaxy makes "a pass" by another galaxy, the galaxies are said to be interacting or colliding. To be ejected from the nucleus of a galaxy implies that the dwarf or quasar or whatever object began its existence in that nucleus and was thereafter ejected (for some inconceivable reason). "Ejection" is an Arpian buzzword that I think needs to be, if not explained, at least well defined.
    A number of posts ago, you agreed that BHs could be ejected from the core of a galaxy by not only many-body interactions, but by two-body interactions. If the BH is ejected with a very high velocity or if it is ejected along a minor axis with little chance to gravitationally capture much of the material of the host galaxy, it may emerge pretty much naked. If it ejected in the plane of the disk of the spiral (in this case), it will have plenty of opportunity to gravitationally capture a stellar population, gas, and dust from the host. Those materials that it could not quite capture, but only draw toward itself only for them to remain in the gravitational sway of the host are arranged as a tidal tail - a concentration of luminous matter that initially traces the companion's path through the host, but eventually will be curved, distorted, an obliterated by differential rotation and other mechanisms.

    Quote Originally Posted by Cougar
    Why do you think a "bull's-eye" is required. I would think any "fly-by" within a very wide range of proximities would quite suffice.
    There are a large number of Arp and VV associations in which the companions lie in jets or tidal streams that extend right back to the cores of the larger hosts. These are either ejection events, in which the companions were slingshotted out of the host, or they were bulls-eye collisions in which the companion somehow passed through the core of the host and dragged material out along the way. The problem with this view is 1) there are way too many of these to be explained by the collision model (lots of low-probability associations) and 2) often the jet extends beyond the companion, supporting the ejections hypothesis more than the presence of a mere tidal stream could.

    Quote Originally Posted by Cougar
    Yes, I recall trying to provide some plausible explanation for these observations. But this doesn't answer my question to you. What is your explanation?
    I have given some plausible answers above. Arp's model is not well-developed in the area of the mechanics of ejection, so I'm not quoting him or supporting him in this regard - I am giving you some plausible methods for ejection that do not require any new physics. You acknowledged the viability of these ideas in post 1325 and now you seem to have recanted, requiring us to re-hash the same old material all over again.

    You are welcome to change your mind, of course, but I am curious why you did so, and what observational evidence you have uncovered that prompted the about-face on this issue. If you have found observations that disprove the ejection argument or weaken it substantially, now would be a wonderful time to share them.

  21. #1401
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    Quote Originally Posted by antoniseb
    There have been a few news stories lately about small galaxies getting consumed by the Milky Way. In the cases shown, there are thin straight tidal streams coming out of the small elliptical core which follow the path of the little galaxy's orbit around ours: one stream leading, and the other trailing behind. It sounds like you have this backward.
    Can you explain the tidal stream extending from NGC 4323 straight back toward the center of M100 by this means? There is no counter-jet. The stream ends on NGC 4323. M100 does not appear to be "eating NGC 4323", NGC 4323 seems to be leaving the scene of the crime, carrying along material stripped from M100, and leaving a trail of material that it was able to attract, but not strip from the gravitational sway of M100.

    http://www.aao.gov.au/images/deep_html/n4321_d.html

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    Quote Originally Posted by turbo-1
    I realize that the dwarf is moving, and it is moving directly away from the core of M100, judging from the nice straight tidal stream pointing in that direction.
    I don't know where you come up with a "nice straight tidal stream" pointing to M100's nucleus. Judging from this image from the Anglo-Australian Observatory, the tidal stream does not appear nice and straight, nor does it point to the center of M100. Let me illustrate....

    Everyone is entitled to his own opinion, but not his own facts.

  23. #1403
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    Cougar, please just click on the link in the previous post and observe the straight tidal stream extending back to the core of M 100. It is a nice thin stream, and the passage of NGC 4323 seems not to have disturbed the outer arms of M 100, indicating that it was ejected at least a bit out of the major axis of the host. Do you have a mainstream explanation of how this tidal stream came to exist?

    http://www.aao.gov.au/images/deep_html/n4321_d.html
    Last edited by turbo-1; 2006-Apr-17 at 12:12 AM.

  24. #1404
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    Cougar, as I mentioned above, you have changed your position on the ejection hypothesis quite remarkably. Will you share with us the observational evidence that prompted this turn-around?

    Quote Originally Posted by turbo-1
    You are welcome to change your mind, of course, but I am curious why you did so, and what observational evidence you have uncovered that prompted the about-face on this issue. If you have found observations that disprove the ejection argument or weaken it substantially, now would be a wonderful time to share them.
    Those of us who ascribe to ATM viewpoints are held to some pretty high standards. At this critical juncture, when dgruss23 and I (and others to some extent) have invested a lot of time and energy to establish some traction for intrinsic redshift via the redshift differentials of bridged galaxies, I hope that antoniseb will require you to adhere to at least a weakened version of that standard, so that you will respond to this question.

  25. #1405
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    Quote Originally Posted by Cougar
    [*]First, the grammar in this paper is atrocious. This alone is enough for this paper to be rejected. A journal editor would likely tell the authors to have it edited and resubmit it.
    The paper has already been published in Astronomy and Astrophysics, v.421, p.407-423 (2004). And really... paper is supposed to be riddled with flaws and you have to settle with a vague comment about grammar?

    Quote Originally Posted by Cougar
    [*]Much more importantly, the authors acknowledge the argument against a posteriori statistical analysis, but then they proceed with such an argument anyway. On page 17 they state, "Statistics have been calculated in several ways for some time concerning the anomalous redshift problem (e.g., Arp 1981, 1999a; Burbidge et al. 1997), in order to assess the probabilities of peculiar configurations. However, many other authors (e.g., Noerdlinger 1975; Sluse et al. 2003) have suspected that many of these calculations are unappropriate. Some authors also say that one should not carry out a calculation of the probability (“a posteriori probability”) for an a priori known configuration of objects (for instance, that they are aligned, or that they form a certain geometrical figure) because all possible configurations are peculiar and unique." This type of probability calculation is much like flipping a coin 100 times, recording the outcome of each flip, and then claiming that the probability of that particular sequence of flips is extremely unlikely, i.e., 1 chance out of 2100. The authors attempt to deflect this criticism by claiming that since their a posteriori argument can be shoehorned into "a physical process in an alternative theory", then it should be exempt from such criticism. Nevermind that such so-called "physical process" is unobserved, unexplained, and unsupported. The authors' defense of their statistical methods is fatally flawed, leaving the "improbability" of their statistical arguments meaningless.
    You're missing the point. Even if the physical process would be completely hypothetical (which it's not in this case), it would be acceptable to check how the situation works under that hypothesis.

    Quote Originally Posted by Cougar
    [*]The authors continue for page after page asserting the improbability of such a configuration. However their entire statistical/probabilistic argument has been fatally undercut by the 2005 paper by Scranton, Menard, et al.. Simply put, new data has come forward, and the conclusions that L-Corredoira, Gutierrez have worked so hard to establish are now seen as simply invalid.
    Lopez-Corredoira & Gutierrez are looking how the situation works under ejection hypothesis. If some later study looks how the situation works under Big Bang hypothesis, it has nothing to do with Lopez-Corredoira & Gutierrez study. If hypothesis X fits the data well, it doesn't mean that hypothesis Y is wrong.

    Quote Originally Posted by Cougar
    [*]In summary, the authors state, "[We have found] several signs of irregularities and asymmetries towards the east. Neither these eastern asymmetries nor the filament towards the east, apparently connecting NGC 7603 and NGC 7603B, can be easily understood in an isolated galaxy..." This appears to be an argument from incredulity, therefore any conclusion reached is drawn from a logical fallacy.
    So where's the flaw? They don't make any conclusions based on this.

    Quote Originally Posted by Cougar
    [*]Are statements like the following appropriate in a scientific paper? "The (possible, although not sure) detection of vigorous star formation observed in the HII-galaxies of the filament, if confirmed, would have a probability 2 × 10−4..."
    Apparently it is according to peer reviewers of Astronomy & Astrophysics. Do you mean that scientific papers shouldn't have any "if something then something" statements?

    Quote Originally Posted by Cougar
    I don't need to try to make this paper look bad. It is bad.
    Even if it is bad, you haven't shown it yet.

  26. #1406
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    Here is an even newer papaer by M. Lopez-Corredoira, C. M. Gutierrez.

    I can't read the PDF version of the papaer, only the abstract, but some might find this useful.

    http://arxiv.org/abs/astro-ph/0509630

    Also, mainstream does Not have to denounce any part of the Hubble flow senario, to allow that there might be some process, as yet unknown, to account for some overly bright entities, to have a possible higher redshift than they should.

    It would seem to me that a vigorous study of M51's "companion" (btw, Turbo, that's my wallpaper too ) VS some of the other possible "companions" could ferret out a factor that is similar to both, even though one supposedly has a higher redshift. Just a thought.

    Edited to add; Great job, both dgruss23 and Turbo 1

  27. #1407
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    Quote Originally Posted by turbo-1
    You acknowledged the viability of these ideas in post 1325 and now you seem to have recanted, requiring us to re-hash the same old material all over again.

    You are welcome to change your mind, of course, but I am curious why you did so, and what observational evidence you have uncovered that prompted the about-face on this issue. If you have found observations that disprove the ejection argument or weaken it substantially, now would be a wonderful time to share them.
    I have pointed out time and again what the problem is with this term "ejection", and you don't seem to have noticed. As I've said before, galaxies and other objects interact gravitationally. Happens all the time. No one disputes this fact.

    Let me ask you this: Is there a difference between interaction and ejection? If so, what is it? Is the set of ejections contained in the set of all interactions?

    If there is no difference, why even use the term ejection?
    Everyone is entitled to his own opinion, but not his own facts.

  28. #1408
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    Quote Originally Posted by Cougar
    I have pointed out time and again what the problem is with this term "ejection", and you don't seem to have noticed. As I've said before, galaxies and other objects interact gravitationally. Happens all the time. No one disputes this fact.
    As I just pointed our a few of posts ago, you didn't have a problem with the possiblility of ejection even quite recently, and now you do. I'm asking you to provide the evidence that you have that negates the possibility of ejection.

    Quote Originally Posted by Cougar
    Let me ask you this: Is there a difference between interaction and ejection? If so, what is it? Is the set of ejections contained in the set of all interactions?

    If there is no difference, why even use the term ejection?
    There is a difference - "interaction" is a broad term and "ejection" is a subset of that, just as "gravitional infall" and "tidal stripping" are subsets. The reason I used the word ejection in the case of NGC 4323 and M100 is that in the deep exposure that I linked, there is a tidal stream behind NGC 4323 pointing back to the center of M100. You neglected to address this and chose instead to post a shorter exposure and trace a spiral out to NGC 4323. This scenario is ruled out by the deep exposure. Can you explain the tidal stream in the long exposure? And please look at the deep exposure. If you wish to rebut the possibility of ejection in this system, please do so using the photograph that shows the tidal stream. The deep exposure that I linked is a mouse-over that superimposes a shallower optical image of M100 over the deep exposure.

    http://www.aao.gov.au/images/deep_html/n4321_d.html

  29. #1409
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    Quote Originally Posted by Cougar
    I have pointed out time and again what the problem is with this term "ejection", and you don't seem to have noticed. As I've said before, galaxies and other objects interact gravitationally. Happens all the time. No one disputes this fact.

    Let me ask you this: Is there a difference between interaction and ejection? If so, what is it? Is the set of ejections contained in the set of all interactions?

    If there is no difference, why even use the term ejection?
    Yes, there is a difference between "ejection" and "interaction".

    In Arp's usage ejection means expelled from the nucleus of the parent galaxy. The mechanism for this ejection is not known. It could be gravitational or it could be something else. Arp has suggested that the core's of these Seyfert galaxies contain white holes that are ejecting the various objects.

    Once an object is "ejected" it may interact with the matter it passes through. In the case of NGC 7603 the hypothesized ejection is in the plane of the disk and so the bridge is thought to be matter dragged out as the ejected objects move outward.

    In the case of NEQ3, the ejection is along the minor axis. In this instance the ejected objects do not significantly interact with the disk of the parent galaxy and so the bridge is dominated by material ejected with the high z objects. And it is observed in the NEQ3 case that the apparent bridge has the same redshift as the ejected objects.

    In the case of this bridges discussion I've generally avoided discussing Arp's ejection hypothesis and focused upon the larger category of interaction - trying to keep the discussion focused as much on observations and as little on hypothesis as possible.

    So the hypothesis we're discussing is simply the hypothesis that redshift does not always indicate distance, that objects of significantly different redshift can actually be at the same distance. In that context we're discussing how bridges are a sign of interaction. Now that applies if we're talking about the specific hypothesis that the bridge results from a gravitational interaction as one object passes by another and that also be applies if the hypothesis is that the interaction is a result of an ejected body disrupting the parent galaxy it has been ejected from.

    So at this point I haven't been trying to distinguish interaction from passing by vs. interaction from ejection.

  30. #1410
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    Quote Originally Posted by Cougar
    Excuse me for getting sidetracked. Let me reiterate: The Lopez-Corredoira, Gutierrez paper is riddled with flaws. Let's list a few of those flaws:
    • First, the grammar in this paper is atrocious. This alone is enough for this paper to be rejected. A journal editor would likely tell the authors to have it edited and resubmit it.

    Except - as Ari has pointed out - the paper has already been published in Astronomy&Astrophysics. Could you point to specific examples from the paper of the "atrocious" grammar? I ask because I want to understand how the grammar has relevance to the substantive scientific evidence in the paper.

    Much more importantly, the authors acknowledge the argument against a posteriori statistical analysis, but then they proceed with such an argument anyway. On page 17 they state, "Statistics have been calculated in several ways for some time concerning the anomalous redshift problem (e.g., Arp 1981, 1999a; Burbidge et al. 1997), in order to assess the probabilities of peculiar configurations. However, many other authors (e.g., Noerdlinger 1975; Sluse et al. 2003) have suspected that many of these calculations are unappropriate. Some authors also say that one should not carry out a calculation of the probability (“a posteriori probability”) for an a priori known configuration of objects (for instance, that they are aligned, or that they form a certain geometrical figure) because all possible configurations are peculiar and unique." This type of probability calculation is much like flipping a coin 100 times, recording the outcome of each flip, and then claiming that the probability of that particular sequence of flips is extremely unlikely, i.e., 1 chance out of 2100. The authors attempt to deflect this criticism by claiming that since their a posteriori argument can be shoehorned into "a physical process in an alternative theory", then it should be exempt from such criticism. Nevermind that such so-called "physical process" is unobserved, unexplained, and unsupported. The authors' defense of their statistical methods is fatally flawed, leaving the "improbability" of their statistical arguments meaningless.
    This a posteriori argument is often used and usually is improperly applied as I discussed here .

    The authors continue for page after page asserting the improbability of such a configuration. However their entire statistical/probabilistic argument has been fatally undercut by the 2005 paper by Scranton, Menard, et al.. Simply put, new data has come forward, and the conclusions that L-Corredoira, Gutierrez have worked so hard to establish are now seen as simply invalid.
    The Scranton paper is irrelevant to this. It was a different analysis with a different purpose and the statistics of that paper are not disproof of the statistics in this paper. The Scranton paper does not rule out there being instances of interacting objects with large redshift differences.

    In summary, the authors state, "[We have found] several signs of irregularities and asymmetries towards the east. Neither these eastern asymmetries nor the filament towards the east, apparently connecting NGC 7603 and NGC 7603B, can be easily understood in an isolated galaxy..." This appears to be an argument from incredulity, therefore any conclusion reached is drawn from a logical fallacy.
    Nice try, but this is not an argument from incredulity, it is an argument based upon physics. When you have a filament or tail - you have a cause - an object that in some way caused that material to be expelled/yanked/whatever from the galaxy.

    When you have an object that is yanked/expelled/whatever, there must have been something that did the yanking. In the case of the NGC 7603 system, the object in the best location to explain the yanking is NGC 7603B. In fact there is no other object observed that is capable of explaining the yanking out of the bridge.

    What they are saying is that the bridge has no explanation if you don't factor in the higher redshift objects because under the interpretation that those other objects are at their redshift distances you have NGC 7603 as an isolated galaxy - a galaxy that has no companion to pull out the filaments that mainstream physics say results from interactions.

    Are statements like the following appropriate in a scientific paper? "The (possible, although not sure) detection of vigorous star formation observed in the HII-galaxies of the filament, if confirmed, would have a probability 2 × 10−4..."
    Are they appropriate? Of course! It's the essence of science. In the realms of religion and politics people make statements with certitude. In science, the level of uncertainty must be acknowledged.

    I don't need to try to make this paper look bad. It is bad.
    You haven't shown that.

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